Conventionally, various kinds of plating treatments have been conducted on objects to be plated such as a wafer for a semiconductor, a printed-wiring board, and the like. As an apparatus for conducting a plating treatment on such objects to be plated, jet-flow plating apparatuses are known.
A jet-flow plating apparatus is generally provided with: an opening on which an object to be plated can be placed; a solution-supply tube for supplying a plating solution toward the object to be plated; and an anode positioned in an opposed manner to the object to be plated, thereby a plating treatment is carried out while a plating solution is supplied through the solution-supply tube toward the object to be plated. Due to capability of conducting a uniform plating treatment on a surface to be plated of the object to be plated and conducting a plating treatment while objects to be plated that are to be placed on the opening are sequentially replaced, the jet-flow plating apparatuses are now widely used as a preferable one for small lot production and automation of a plating treatment.
Although the jet-flow plating apparatus has the above-described advantages, a film, for instance a black film or the like, to be formed onto a surface of an anode may be broken away into a solution and become impurities to flow in a plating solution supplied toward an objective to be plated, thereby possibly causing a negative effect on a plating treatment. Additionally, air mixed in a solution or bubbles generated from an anode sometimes reach a surface to be plated, thereby inhibiting a good plating treatment. In this jet-flow plating apparatus, therefore, a diaphragm for separating an object to be plated and an anode is arranged within a plating tank (see Patent Document 1: Japanese Patent Application Laid-Open No. 350185/1999).
The jet-flow plating apparatus having a diaphragm arranged within a plating tank as shown in Patent Document 1 resists a negative impact exerted by impurities generated from an anode, prevents wastage of plating additive agent which occurs when an insoluble anode is used, and furthermore surely overcome a negative impact exerted by air bubbles generated from an anode.